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High-performance XPS fanfold underlayment designed for re-siding and wall sheathing. Moisture-resistant and easy to cut, it delivers R-1 thermal performance in a flexible, square-edge format ideal for smooth, energy-efficient cladding prep.
Please check the Product Data Sheet Here
| Specification | Details |
|---|---|
| Insulation Type | Foam Board Insulation (XPS) |
| Insulation R-Value | R-1 |
| Compressive Strength | 25 psi |
| Thickness | 0.25 in (1/4 in.) |
| Width | 48 in |
| Length | 50 ft |
| Coverage Area | 200 sq ft |
| Edge Profile | Square Edge |
| Faced or Unfaced | Unfaced |
| Interior/Exterior Use | Interior (re-siding sheathing) |
| Insulation Location | Re-Siding |
| Compatible Install Surface | Concrete, Plywood, Wood |
| Number of Pieces | 1 |
| Pack Size | 1 |
| Product Weight | 13.2 lb |
| Sheathing Type | XPS |
| Warranty | Limited Lifetime |
| Certifications | GREENGUARD Gold; ENERGY STAR Seals and Insulates listing |
| Environmental Note | Manufactured with a blowing agent with >80% reduction in global warming potential vs. legacy FOAMULAR XPS |
Q: Can this be used under new siding?
A: Yes, it’s designed as a re-siding fanfold underlayment to create a smooth, insulated surface.
Q: Is it suitable for damp areas?
A: The XPS foam resists moisture and maintains its R-value after exposure to water.
Q: Do I need special tools to install it?
A: No. Panels are easy to score and cut with common utility knives and install with standard fasteners or foamboard adhesive.
Q: What are the dimensions and coverage?
A: Thickness 1/4 in., width 48 in., length 50 ft; covers approximately 200 sq. ft.
Q: Is it soundproof?
A: No, this product is not rated for STC and does not provide soundproofing.
FOAMULAR’s fanfold underlayment creates an impeccably smooth canvas beneath fresh siding, elevating curb appeal while quietly boosting energy performance. The flexible, square-edge design glides over exterior walls for clean lines and a refined finish. Pair it with crisp fiber-cement or modern vinyl profiles to achieve a tailored, contemporary look. It’s a smart, luxurious layer that makes exteriors feel deliberate and beautifully composed.
Upgrade your re-siding project with FOAMULAR fanfold underlayment for smoother walls and lasting energy savings—add to cart today.
Ships within 48 hours · Estimated delivery Aug 12 - Aug 17
US$40
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